Hi Henry, I advise you to use Autosync Dropbox app. It is very helpful for this issue. I used it for a long time. You can find it here, https://play.google.com/store/apps/details?id=com.ttxapps.dropsync
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Hi ajthen There is a very simple trick. Uninstall Dropbox and install it again. While installing, it asks if you agree to link camera photos to Dropbox, tick the box. Now, it is done. All photos will go to Dropbox automatically. Hope that this can help you.
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Hi ageorgakis, I think your problem may be due to incorrect uploading of your photos to Dropbox. Sometimes this happened due to problems in your internet network. This problem causes corruption for a part of the photo data while uploading. Try to use strong high-speed internet network, in a new folder. I hope that can help you. Have a nice day.
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